Maintenance and/or upgrade activities on computer systems are ideally performed when the computer systems are under-utilized. In some computer systems, it may be assumed that certain periods of time will have a relatively low impact on a computer system, such as during the night, and so such activities may be scheduled for predictable low-use periods. In other computer systems, such a predictable or regular usage schedule may not exist. In these cases, educated guesswork by humans may be used to determine a future window of time in which to schedule the activity. Unfortunately, such guesswork is too often wrong, and the resulting impact on a computer system during high utilization can result in an inconvenience or worse for users of the computer system.